The Murderer of Danville
by bilaterus
Summary: Strange deaths have been happening in Danville, and Isabella thinks she knows who's behind them. But suddenly, she finds herself in a house of horrors, trapped by the murderer. Will she make it out alive? Viewer discretion advised.
1. Chapter 1

**As part of my bid to write as much variety as possible, I bring you a horror story that Galaxina-the-Seedrian and I discussed briefly, aages ago. I hope it chills you to the core.**

* * *

"Ferb is a hit man!"

Phineas's usual cheeriness turned into confusion. "What?"

"Ferb!" Isabella repeated urgently. "He's a hit man!"

It was not how Isabella usually entered the backyard. Phineas took a moment, studying Isabella's expression, and saw she was genuinely panicked. And she was. Isabella wasn't one to jump to conclusions, especially with an accusation as serious as murder, but the thought had occurred to her in a flash that very morning, and as much as she turned over the facts in her mind, they only confirmed it.

Phineas, however, was not so easily convinced.

"Isabella, I never thought I'd say this, but you've gone totally crazy."

"Hear me out," Isabella said, looking around nervously to make sure Ferb was not in the vicinity. She then produced _the Daily Danville _and pointed at the front page headline: 'French Ambassador Killed: Situation Described as Fishy'.

"He and Mayor Doofenshmirtz were visiting the Danville Aquarium when the glass to the shark tank broke and he was ripped to pieces by a great white!"

A shadow fell across Phineas's face. He studied the newspaper article intently for a moment. "Well... despite the delightful nautical play on words in the headline, the article suggests it was just an accident," Phineas said seriously.

"Maybe so," Isabella admitted. "But take a look at yesterday's paper!" She swapped that day's _Danville Times _that she was holding with the previous day's. "Look! 'Visiting British Dignitary Hit By Freak Lightning Strike… 27 Times'! And the day before that, 'Chocolate Factory Tour Turned Sour When German Ambassador Is Killed By Exploding Chocolate Bar'**!**"

"But Isabella, those were all described as accidents," Phineas said. "Albeit highly unfortunate ones for the people involved. And even if they weren't, there's no evidence Ferb was behind any of it!"

"Come on, Phineas. Who else would kill people like this? It's totally Ferb's style!"

"Nah, Ferb wouldn't hurt a fly," Phineas said. "Oh, unless it was some sort of evil bionic fly…"

"And you two have been doing more secret solo projects these days," Isabella continued, undeterred. "I'll bet his 'projects' have been assassinations! We need to get to the bottom of this!"

It really was a horrible accusation to make, and Isabella desperately wished it wasn't true. But it all lined up. What was that quote? _When you have eliminated the impossible, whatever remains, however improbable, must be the truth._ And it seemed to Isabella that there was only one improbable truth left. And as much as she loved him as a friend, Ferb did fit the bill, what with his shifty eyes and silent, secretive demeanour.

And if it was true, then that put her and Phineas in more danger with each passing second.

The red-headed inventor was silent, deep in thought for what felt to Isabella like an eternity. Then, finally, he nodded, in what seemed like acceptance. "Ok. Have you told anyone else about this yet?"

Isabella relaxed slightly, now that Phineas was on board. "No, just you." Ferb was his brother, so Isabella had decided that he deserved to hear her suspicions first. And if anyone could help her, it was Phineas.

"I see. Well, I need to see a man about some parts for one of those solo projects of mine," Phineas said, his expression brightening again as he made to leave the backyard. "But right after I get back, we'll get the gang together, perhaps sans Ferb, strange as it'll be, and get to the bottom of this."

"Oh, er, ok…" Isabella said. She then realised that Phineas was leaving her alone, possibly a stone's throw away from Ferb. "Oh, Phineas, er, mind if I come with you?"

"No!" he said, a little suddenly. "I mean, it's actually a surprise for you!" he scratched his neck anxiously. "And don't worry, even if Ferb was secretly evil, he wouldn't get you out in broad daylight in our backyard. That'd be way too boring!"

"I guess... where is he, anyway?"

"He's just inside. Relax, Isabella, Ferb's not a psychopathic murderer. Trust me," Phineas winked.

Isabella may have been more reassured by this had she not felt the gaze of a shadow from a bedroom window.

"Stay right here," Phineas instructed, and he then rushed out of the backyard, unusually quickly.

Realising her heart was racing and that there was nothing to worry about, Isabella slumped against the tree. Phineas was right: Ferb wouldn't get her here and now. Besides, she was a Fireside Troop leader. When she had her guard up, she could do anything. Phineas would get back and everyone would come together and they'd all get to the bottom of this.

_And then Phineas will present his secret project, one just for me!_ She squealed inwardly. _Could this be the day?_

She allowed her mind to wander in the field of possible inventions and timelines. _Would it be a romantic journey above the clouds? A statue of us, carved out of marble? A giant bouquet of flowers? Or perhaps he' s simply going to take my hand in his, stare lovingly at me with those great, wonderful eyes, click his fingers and whisk us away to have that Paris love scene that I've always wanted..._

* * *

Isabella stirred with a groan, her eyes still closed. Her head throbbed painfully. The ground felt hard to the touch and the air smelled musty and damp, in stark contrast to the soft grass and fresh air of the backyard.

Strange, since Isabella didn't remember falling asleep at all, let alone in a place like this.

She concentrated on any memories that might explain how she got here, only her mind was blank past Phineas leaving her in the backyard. But her throbbing head suggested that despite Phineas's reasoning, Ferb must have done something after all, knocking her out and leaving her here.

But where was 'here'? She could hear the humming of some technology, adding evidence that Ferb had a hand in where she had ended up. She'd have to keep an eye out for him. Slowly, unaware and afraid of what she would see, her eyes opened... to meet an unexpected pure darkness.

It was at this moment she was tempted to scream and call out for help. But then she remembered she was Isabella Garcia-Shapiro, leader of Fireside Troop 46321, and now was not the time to panic. Instead, the Fireside Guide to Handling an Unfamiliar Situation appeared in her mind. Step 1 was to keep composed. She should not panic. Step 2 was to assess the situation properly.

Isabella realised she was curled up on the ground and carefully made to stand up. She could see a little into the darkness now, her eyes having adjusted. There seemed to be pickle jars filled with liquid of some sort on various pedestals around the room, translucent and eerie tubes connecting to and from them. She stared in bewilderment, turning to take in the rest of the room.

Then, suddenly, the lights flashed on, and she came face to face with a single human eye, looking right at her.

The grisly body part was floating in the jar, suspended in the unidentified liquid. Isabella gasped and staggered backwards. She crashed into another pedestal. A loud beep sounded and Isabella felt a liquid trickling down her back. The smell of iron filled her nose and she spun around sharply, fearing the worst of the fluid. Blood. It covered her back and shoes and was still spilling out from the tap she had triggered.

_What is this?!_

Desperately, she tried to escape the spreading pool of crimson on the floor. Backing away from it past the various pedestals, she could now see their macabre contents. A severed human hand. A person's nose. A foot. Hearts and livers, stomachs and intestines, all stored in jars like some mad scientist's trophy room.

Isabella felt sick to her stomach. She wished desperately for this all to be a dream, but the sticky blood on her clothes and hands and the ache in her back confirmed that this was all too real.

_This must be one of Ferb's secret places, _Isabella realised. She leaned on one of the pedestals, eyes shut, breathing hard to regain her composure. It took several minutes before she was able to keep her eyes open without wanting to throw up.

_Ok, there must be some way out of here, right? _she tried to convince herself. _And I won't find it by waiting around… _Slowly, she began walking through the lines of pedestals, looking for a door or exit.

She found a door, but she also found a desk, piles of papers with unintelligible markings stacked on top of it. There was also a nondescript notebook positioned unusually neatly in front of the desk chair. A compelling curiosity overcame her and she flipped open the notebook… and then immediately flipped it closed, upon seeing a coloured sketch of a disfigured person with body organs highlighted, shuffled around, annotated...

_Ferb's researching zombies? _The thought made Isabella shudder. Well, it certainly explained this room filled with body parts, though it wasn't an explanation that gave Isabella any relief.

Then the entire floor jolted.

Instinctively, Isabella grabbed onto the desk, as the room trembled. Though she could not see them, the tinkling glass and sloshing liquid created the vivid imagery of the suspended human organs squelching around in their jars around her. She tried to shut out the imagery and prayed for it to end. Then, as suddenly as it all began, it ended, with a large ding, as if she was in a mall elevator that had just reached the correct floor.

Isabella wasn't sure how much more she could take. Her heart was beating a thousand times a minute. All she knew was that Ferb couldn't, and wouldn't, let her escape, now that she knew what she did. But at this point, she just wanted this whole ordeal to be over. One way or another.

But she then heard a voice that was to change everything.

"Hey, Isabella!"

"Phineas?" she exclaimed, instinctively moving towards the sound of the voice. Relief washed over her; Phineas would save her. He would make this all go away.

"I take it the anaesthetic has worn off?"

Isabella realised the voice was coming from a speaker, and, looking up, spotted it in the corner of the room. A small microphone was below it and, judging from Phineas's response time and questioning, he could hear her too.

"Phineas, thank goodness you're here! Ferb dumped me into this horrible room filled with-"

"Woah there Isabella. I don't mean to cut you off, but if you tell me where you are, it'll spoil all the fun!"

"Wait, what?" Isabella asked, bewildered.

"And I already told you, Ferb's not responsible for any of this. He's just too nice!"

"But who else could it be?" she said exasperatedly. "All the murders were creative and meticulous, and Ferb is the most creative and meticulous person there is! Well, except..."

Isabella froze. _Except the one other person who was at least as creative and meticulous as Ferb Fletcher._

"Ah, you've finally got it!"

Isabella turned slowly, in utter disbelief, towards the speaker. Phineas's voice hadn't changed in tone at all, but suddenly it sent icy cold shivers down Isabella's spine.

_No… no, it can't be… _

"Yup, it's me!"


	2. Chapter 2

**Phineas makes quite the chilling psychopath, don't you agree? **

* * *

_It couldn't be Phineas. It just couldn't be._

"Wow Isabella, you sound just like Ferb right now! Because you're not actually saying anything yet I know exactly what you're thinking. But I'm afraid it's true. "

There it was again: that casual, easygoing voice that had gone from warm and inviting to chillingly disturbing in a single moment. A million questions flooded Isabella's mind, but she couldn't articulate any of them.

"I had better explain what's going on. You see, someone hired me online to destroy Mayor Doofenshmirtz's career without being detected, and I thought it was a great opportunity. I mean, just think of all the creative possibilities there are of diminishing someone's reputation!"

"So you settled on assassinating visiting dignitaries?" Isabella asked, already knowing the terrible answer.

"Yup! Without being detected, of course. But that's just part of the challenge!"

"Does… does Ferb know about this?"

"Well, he knows I'm doing _something_. And I know he's doing something too, but it's a secret. I'd tell you, but then I'd have to kill you… hehehe, 'kill you'. I mean, I have to anyway, but I'd better not tell you what Ferb's secret is. A promise is a promise, after all."

Isabella could almost imagine him wiping a tear from his eye as he chuckled at the joke he'd just thought of. She felt like laughing too, like a madwoman, at the sheer skew of Phineas's morals, that he was above breaking a promise to his other childhood friend just as he was about to kill her. The entire thing was utterly crazy.

"I mean, it's nothing personal, Isabella, but I can't have people knowing about what I do. That'd compromise the entire mission. But don't worry, I came up with a way that makes it fun!"

"Phineas, I can't think of a single way that _killing me _could possibly be fun!" Isabella shrieked, in desperate hysterics. "I never thought I'd say this, but you've gone totally crazy!"

"Hear me out. See, we're currently in a building of my design. It's made out of rooms that are like blocks that can rearrange themselves and connect to each other in different ways. I had the building drop us both into random rooms, and my job is to find and disintegrate you with my particle blaster as soon as possible while you try to hide and the building shuffles us around! Pretty cool, huh?"

_No, no it isn't!_

Isabella wanted to break down and cry. How, _how _could she live side by side with someone for so long, knew inside out, and have such a crush on no less, and not realise he was capable of all this unspeakable madness?

And he was going to do more. Isabella had no doubt in her mind that Phineas would blast her when he got the chance. He was a monster, a smiling psychopath. She still didn't fully believe it, her very mind didn't _want _to accept it, it seemed horribly wrong, but even as she thought of those words they made a twisted kind of sense at the same time, these words that went completely at odds and also perfectly aligned with the profile of her smiling neighbour, who lived to be creative and seize the day. Whose motto in life was the belief that you can achieve anything if you put your mind to it.

Even murder.

She couldn't let him get away with it. She _wouldn't _let him get away with it. For the second time, she reminded herself that she was Isabella Garcia-Shapiro, and she was a fearless Fireside troop leader. Well, she was supposed to be fearless. Isabella became acutely aware of how much her knees were shaking. And the tears that had escaped her eyes when she hadn't noticed.

Numbly, she began moving towards the room's exit, gingerly avoiding as much of the blood on the ground as she could. Her mind was mostly blank, perhaps as a defense mechanism. Maybe she was moving because she subconsciously didn't like the idea of doing nothing while Phineas closed in on her. She laid a hand on the doorknob, but a small shuffling noise on the other side of the door made the hairs on the back of her neck stand on end.

Her mind then suddenly went into overdrive. _What was that? Is it Phineas?_ She listened hard, pressing her ear against the door. Nothing. _Did I imagine it? _If she did, then she'd be one step closer to the exit, but if it was Phineas...

The danger paralysed her. The doorknob was loose to turn but now it might as well have been superglued in place as far as Isabella was concerned. There was no way she could turn it knowing Phineas may be on the other side.

"Wow, three rooms already and I've still not found you! Isn't this exciting?"

If Phineas really was in the other room, then surely she'd have heard his voice through the door, but Isabella only heard it through the speaker. Or perhaps the walls were better soundproofed than their appearance suggested? Either way, Phineas's words were a sharp reminder to Isabella that she was getting nowhere fast. Mustering all her courage, Isabella took a deep breath and, with one motion, turned the doorknob and pushed the door open.

* * *

Isabella braced herself for the worst as the door swung open. But apart from a foul, yet strangely familiar, odour, nothing hit her. And the room was pitch black. Her body relaxed slightly and Isabella was in no real position to counter that. She tried to remind her body that the darkness could still be hiding anything.

_The lighting is motion-sensitive. _she thought, without warning. She had no idea how her subconscious thought of it, but as she thought about it, she realised it made sense. It explained why the lights had suddenly turned on earlier, and why she hadn't seen any obvious light switches. Again, her body wanted to be reassured by this, as it meant that there was nothing in the room which was moving. Which meant no Phineas.

But as the room she was currently standing in had showed her, there could be any number of unspeakable unmoving horrors just waiting in the darkness. And it was also possible there was something in there, but it was not moving very quickly. Something had made the sound she had heard, after all. Isabella just hoped that it was a machine of some kind.

But there was only one way to find out for sure. Tentatively, Isabella reached a hand in, and waved it vigorously.

The light slowly flickered on. Isabella could make out the features of a large bookcase, with books scattered all across the floor. The intensity of the light reached its peak and there was a loud groan from the left hand corner of the room. Isabella spun around sharply. What she saw made her leap out of her skin.

Or rather, _who _she saw.

It was Buford. But not the usual pale-skinned bully she knew. This Buford wore his distinctive black skull shirt, but it was torn and dirty, and revealed molding, fungal arms. His face was horribly disfigured and long lines of stitches held together patches of his skin, in a Frankensteinian style. He groaned, recoiling from the bright light, and began staggering towards her with surprising speed, dragging a partly broken leg with him.

Isabella leapt back into the Jar Room and slammed the door shut. But it didn't close. She looked down to see Buford's stubby arm poking through the gap, his hand grasping at the air. Isabella felt his finger brush against her and she recoiled, slamming the door with even more force. Buford groaned in pain. But the door still wouldn't shut.

Then, as suddenly as before, the entire room shook under Isabella's feet. There was a huge mechanical lurching sound, and she felt everything accelerating to the left. She pushed her back against the door, digging in her feet, to prevent the force flinging her across the room. Then, as before, a loud ding indicated it had stopped.

Isabella placed a hand on her chest, her heart now beating a thousand times a second, and breathing at least as fast. She had to get her bearings again. As her mental state returned to normal, she realised that the door she was leaning against had shut fully. Buford must have been pulled away by the room shift.

She sunk to her knees. That incident had exhausted her mentally and was taking its toll physically. The difficulty it indicated in even moving through one room now loomed over her: if every room was going to be as traumatic as these two, then she was doomed to stay in this room for the rest of her life. Which would be until Phineas found her.

Well, she had lasted longer than Buford had. A horrible image arose in Isabella's mind, one of Phineas poring over Buford's corpse laid out on a mad scientist's operating table, like something out of a bad horror film, as the crazed red-headed inventor looked over his specimen with the same curiosity and fascination with which he regarded a new puzzle game. In her mind, Phineas then took a knife and, with all the precision of a master surgeon, sliced the skin apart to get a hold of the grisly insides, biting his lip in concentration, or perhaps with his tongue slightly out and an eye closed as he focused in his unique, irresistible style...

Isabella began sobbing. She hated that her mind was still crazy about Phineas. She hated that she could do nothing but sit, paralysed, wanting to cry out of despair and lost love. Why, _why _was her mind still fantasizing about being right beside him as he began the operation?

A creaking from the other side of the room interrupted her thoughts. She immediately recognised it as a door swinging open and her body instinctively made for cover without a sound, positioning herself behind one of the stands supporting the jars. It was a good position, one that if Phineas walked right through to the door she was just at, he would not see her.

Isabella realised with a start that there was no chance of Phineas doing that. The lights were on. That indicated to Phineas that she was in there, if they really were motion-sensitive. Even if they stayed on for a long time after detecting any motion, Phineas would deduce that she might be in that room, and look around thoroughly, surely finding her if he did so.

It wasn't reassuring, and Isabella could already hear slow, measured footsteps entering the room. But then she looked down and saw something that really made her heart sink.

Footprints. A trail of red footprints leading right to the spot she was crouching in now. They were hers, of course. Footprints left by her as she panicked, oblivious to the crimson blood clinging to her shoes and leaving traces of her path.

So this was how it ended. Killed, while cowering in fear, by her best friend and crush. No dream future with Phineas, with a house and children, which was all she had ever wanted. So much for the words she had held onto since early in the summer: "Aunt Isabella! That means I'm going to marry Phineas!"

And for some reason, the joking "or Ferb" addition swam into mind and stayed there for a few seconds.

The footsteps began inching closer, after having paused momentarily about a meter away. So Phineas had seen her footprints and was coming for her. She had resolved to go with a fight, where there was a slim chance she could knock Phineas's weapon out of his hands and overpower him. But she couldn't stop shivering at the thought of the much more likely outcome.

The footsteps reached her.

With all the adrenaline she could muster, she leapt at her attacker, knocking him to the ground, throwing punches and kicks blindly, one of which connected clean on his cheek. He recoiled. She raised a fist, to hit him squarely in his large flat nose.

_Flat nose… Ferb?! _

She looked down in disbelief. She was indeed standing over Ferb, who had raised his arms protectively. She was breathing heavily again, and Ferb was looking at her with terror in his eyes. Well, no wonder. She imagined the scene from Ferb's point of view: that in a flash, his crazed, blood-covered friend began relentlessly attacking him, likely with a maniacal look in her eyes. Isabella backed down, and Ferb slowly rose to his feet, still a little wary of her. He was clutching a ray gun of some sort.

"Ferb," Isabella began. "What are you doing-" but Ferb signalled her to be quiet and pointed at the microphone in the corner of the room.

Ferb slowly got over the shock, and his expression changed to one of sadness and pity. He had come to rescue her, Isabella realised. She had accused him of murder, and now had viciously attacked him, but he was still going to go against his step-brother, his other half, to save her. Because he was Ferb. Tears welled up in her eyes as her body accepted the ordeal was over, and she finally succumbed to it, sinking to her knees as Ferb rushed to comfort her in a warm embrace.

Ferb would save her. Ferb would make this all go away.

But through her vision blurred by tears, a figure appeared in the doorway of the other side of the room. Ferb too spun around, to see his step-brother in the doorway.

Phineas grinned. "Found ya!"


	3. Chapter 3

"You know, Ferb, I'm actually glad you showed up," Phineas said, almost conversationally. "I think this would've been a little boring otherwise."

Ferb raised his weapon, a ray gun identical to Phineas's, in response, a determination in his eyes that Isabella had never seen in them before. The red-headed brother was unfazed, however, and merely continued talking as if they were all together in the backyard like any other day.

"You look quite cool in that pose, bro, like you're a hero protecting the romantic lead," he grinned. "It really puts your secret project in perspective. Anyway, are you _sure _you don't want to join me? I'm telling you, assassinations are even better than inventing things! You get to be so creative, and when you pull it off, it's… it's just such a rush-"

The motion-sensitive lights chose that moment to flicker off. Immediately Ferb fired a blast in Phineas's direction, the bolt casting a momentary green glow on the room. It collided with one of the pedestals and liquid and shards of glass sprayed everywhere, and as Isabella's mind registered what was happening Ferb pulled her into cover behind a pedestal.

The lights re-activated. Tentatively, Isabella poked her head around the pedestal, but Phineas was nowhere to be seen.

"I'll take that as a no, then," Phineas's voice rang out. Isabella quickly ducked her head back behind the pedestal she was taking cover behind as a powerful energy blast missed her by inches. Phineas and Ferb then began exchanging fire, one after the other, jars shattering and spewing their horrific contents of body parts and liquid everywhere.

"How about you, Isabella? We can be like Bonnie and Clyde, only, you know, hopefully with less death."

Isabella's heart skipped a beat. She'd fantasized long about being the Bonnie to Phineas's Clyde, but only ever briefly, in a romanticised Alternate Universe where the only thing that mattered was their mutual love. But hearing it proposed by Phineas as a real possibility was something different altogether.

She couldn't take it. To take it would be madness. _Phineas_ was madness. But…

"If… if I accept," Isabella found herself saying, slowly. "Would you let Ferb go?"

There was a break in the exchange of fire as Phineas seemed to consider this. "Well… I suppose I could do that. Since it's you, Isabella."

The last few words sent an involuntary shiver up her spine.

"It's not him." Ferb's voice rang out among the silence. "It's not the Phineas we knew and loved."

The words were like a splash of cold water in the face, snapping Isabella out of the confused trance she had fallen into. It was like a switch had been flipped in her mind. Ferb was right. Of course Ferb was right. She had to do something about this.

Carefully, Isabella peered around her pedestal, watching Phineas poke his head around his cover to fire at Ferb before ducking back into safety again. Where before she felt a fluttering when she saw his face, now she felt only a determination to take that monster down.

She searched around her for a projectile, and her hands found a human heart. She grabbed it immediately, ignoring its slimy texture. The heart was much lighter than she thought. Her own heart started to beat faster in anticipation of her plan.

Phineas's face appeared once again. _Pitching patch, don't fail me now, _Isabella prayed. as she hurled the heart directly at Phineas.

It connected. For a second, Phineas turned, distracted, and Ferb seized the opportunity to fire a final stunning shot with pinpoint accuracy at his step-brother's chest. Surprise flashed momentarily on Phineas's face, then he slumped to the floor, finally still.

"_Hey guys!" Phineas said cheerfully, from the TV screen. _

"_It's lovely to hear from you again, Phineas," Linda said. "It's like you're right here with us."_

_It had been a week since the government agents had come for Phineas. It had been completely without warning; Linda had come home, where two burly men in black suits were waiting, who informed her that their son was needed for a top secret government mission. Linda still scarcely believed it, and indeed wouldn't believe it if Phineas didn't call home regularly to assure her that everything was alright. _

"_Good job on the wiring, Lawrence," Linda added. "I didn't know you could get his calls to appear on the TV like that."_

"_Well, Ferb did it, really," her husband said bashfully. "I just supervised. Where is Ferb, anyway?"_

"_He's upstairs," Candace said. "Probably because he can already communicate with Phineas, by one of their dumb inventions. Or telepathy."_

"_We don't have telepathy, sadly," Phineas said. "But it's alright. How is everything back at home?"_

_..._

[be aware it's been a week so far. replace searching of downstairs by what she usually does with Ferb (she reads). shuffle stuff around a bit.]

The nights were the hardest. Isabella no longer ended the day spent, yet happy, after a day of spending time with the Fireside Girls or Phineas and Ferb, and then drifting off to sleep with visions of Phineasland or new inventions. She now had to confront, alone, the memories of the terrible incident, exacerbated by the darkness, until she fell unconscious, out of exhaustion, where in her nightmares, Phineas continued to haunt her.

Not that spending time with people was any easier. She couldn't help but be suspicious of everybody, even the Fireside Girls, after learning that anybody could be a psychopath. She only spent time with a few people now. Her mother, for one. Pinky, too - though not technically a person, she knew Pinky had no secrets from her. And there was one more person.

Isabella strode through the door of the Flynn-Fletcher house, without ringing the bell. She spent most of her days here now, in the guest room with Ferb. Mostly, they did their own thing: she would get lost in a book, and Ferb would doodle or use the guest room computer to keep himself distracted. She quickly crossed the passageway and took the first step onto the stairs.

When she froze. Phineas was standing at the top of the staircase.

"Hey Isabella. How're you doing?"

The colour drained from her face. There was no way Phineas could be here. He was locked in a secure facility that Ferb himself had invented to keep him sealed away. He could call home, so that his disappearance could be explained, but if he was to escape, an alarm was supposed to alert Ferb and her immediately.

He began walking casually down the stairs towards her.

"Isabella, what's wrong?" he asked, in mock worry. "You look like you've seen a ghost."

Isabella blinked, and looked up at Candace's face. "Are you alright?" Candace asked again.

Isabella clutched her head, collecting herself for a moment. _Candace as Phineas? What kind of hallucination is that? _She exhaled the breath that she had unconsciously been holding in. "I'm… I'm fine," she managed..

Candace stared at her for a moment, worried. "Well if you say so. Ferb's in the guest room, if you're looking for him. Do you know why he's always in there?"

"Not really," Isabella lied.

"Shoot, I thought you might. Well, if he says anything, let me know." She patted Isabella on the shoulder sympathetically, then continued past her. The girl sighed and made her way up the stairs to the guest room.

Unlike Candace, she knew exactly why Ferb was staying away from his room. It had been hard enough for her to enter her own room again, given all the Phineas-worship stuff there was in it. She imagined it must've been doubly bad for Ferb, given that literally half the room belonged to Phineas himself. She knocked on the door of the guest room.

Ferb opened the door. His face looked gaunt, as if he'd aged several years in a couple of days. Isabella knew her face had similar features. They exchanged smiles. Ferb let her in and she slumped onto the couch, while Ferb resumed sitting at his desk. She allowed the feeling of serenity to wash over her, dealing mentally with the hallucination she had experienced minutes before, before picking up her book and continuing from where she left off.

Several hours later, the setting sun's red glow shone through the window. Isabella finished her book and sat up, then wandered over to look over Ferb's shoulder at what he was doing. The desk was covered in papers, blueprints that Ferb had drawn up to various levels of completion over the past few days. Even now, Ferb was doodling another idea for an invention, though he was barely focusing on it.

It was a huge improvement over how he had been a week ago. He would sit at the desk, pencil poised to draw, frozen in that position, as memories of him doing the same with Phineas overcame him. He'd remain that way until Isabella laid a hand on his shoulder and his body relaxed.

Yes, ultimately, that was the reason why she came over. Her presence soothed Ferb as much as Ferb's presence soothed her.

Isabella's eyes fell on a notebook, identical to the one in the mansion. It had spooked her at first, but now, after a week or so, her curiosity was stronger than her fear. She picked it up and flicked it open to a random page.

It was a sketch of her. In Ferb's handwriting, annotations filled the space around, detailing her likes and dislikes, habits and mannerisms. On the other pages were plans. Romantic dinners. Movie nights. A picnic for two, but on a rainbow instead of the ground. A trip to Niagra Falls.

"So this was your secret project," Isabella said. "Plans to get me and Phineas together. No wonder he was confused."

Ferb nodded in confirmation, and Isabella chuckled.

"Oh my gosh, he must've thought you had a crush on me! He really was oblivious right to the end, wasn't he?"

Ferb rolled his eyes, grinning, as if to say 'you have no idea'.

"Oh, I heard Buford got back home today," Isabella remembered. "And his mom said his diction and body odour have both improved."

This got a snort out of Ferb, which in turn caused Isabella to laugh. She hadn't had a proper laugh in what felt like an eternity, and it felt good.

"I really am chatty today, aren't I, Ferb? I think it's because you're just so good to talk to." She lay back onto the couch, thinking. "Phineas was right: it's not what you don't say, it's how you don't say it."

"And I'm British," he added, with winking.

She laughed, and for a brief moment, everything was alright with the world. But then reality kicked back in, and darkness gathered outside the window, waiting to attack them both once again."

"Hey Ferb?" Isabella said. Ferb turned to face her, inquisitively, in response.

"Can I sleep over here tonight?"

Without a word, Ferb left the room. Seconds later, he returned, with a pile of blankets, atop of which was balanced a tray of assorted goodies, chosen to accompany an evening tea.

"Crumpets or toast?" he asked.

_*A few weeks later*_

"Friends, zombies, Irving," Isabella said, Ferb beside her, to the assorted crew of people that had assembled in the backyard, which included the Fireside Girls, Buford and Baljeet, and their friendly neighborhood stalker. "We have gathered you here today to take part in an exciting project."

"Braaains?" Zombie Buford groaned in an almost hopeful tone. The Fireside Girls looked at him worriedly.

"Should we be worried?" Katie asked nervously, as the girls edged away from the zombified bully.

"It is quite alright, he is harmless," Baljeet said. "His vocabulary is highly limited, due to tinkering in the Broca's Area of his brain. Plus, he is technically Frankensteinian, rather than a zombie, although even _more_ technically, since Frankenstein was the name of the inventor rather than the monster itself-"

"Laaame," Buford groaned, and he tried to take a bite out of Baljeet's arm. The Indian boy retracted his arm in disgust.

"Ugh, Buford! Did you not just hear me explain how you are a frankensteinian monster and not a zombie?"

"Saaame," he droned, shrugging.

"Anyway," Isabella said. "We've already ordered the parts, and they should be arriving any minute now."

"So we're building something?" Irving asked excitedly. "Ooh, I've waited for this day for so long! What're we building?"

Isabella hesitated, until Ferb held her hand tightly, reassuringly. She smiled.

"We're building a rollercoaster."


End file.
